Answer / kavitha

If the supply is given ,the voltage increase form low to
high level .the current also increases so to reduce the
high starting currents & protect the motor we use starter.

Answer / priya

Starters are used to limit high currents during starting by adding resistors in series with armature circuit which are excluded gradually when the motor speed increases. High starting currents are due to
1. In case of DC motor, initially back emf(E) is zero therefore I=(V-E)/Ra becomes V/Ra. Generally Ra armature circuit resistance is very low hence I is very high during starting. When speed increases back emf increases and I reduces therefore resistors can be excluded.
2. In synchronous motors starters are not used

Answer / saranya natarajan

To limit the starting current
Initially all resistances will be included to limit the
starting current. Slowly the resistances will be excluded
one by one and gradually the current increases and motor
runs in rated speed.

Answer / ravi raj

starter gives normal rating current & voltage to start the
motors, to gives over load the starter is triped.

Answer / mohammad rashid

The motor stsrter will trip an overload relay the current
to the motor is excessive, It will also remove power from
all conductors to the motor.

Answer / pradyumna chandra panda

to provide OVER LOAD RELEASE COIL(Relay) to save the moto winding from more current than rated.

where is used dc volage transformer,and what is highest capacity of transformer

2 Answers  

When connecting a loaded powerplant to the Huge grid,what are the factors to be considered and how the VAR flow will affect the system?

1 Answers  

Why we are going for converter transformers for DC drives application instead of distribution transformer?

0 Answers  

I have 12MW gas engine based power plant its running parallel with grid. my problem is When cpp run in island mode(without geb) that time geb transformer power factor is 0.2 lagging. When cpp run with parallel that time power factor is 0.94 lagging So how can i maintain power factor ofgeb transformer in island mode 0.9 lagging?

1 Answers   SPCL,

what happen if one of 3-phase line has a much higher load when we are using delta to star transformer? how we can over-come from that?

2 Answers   Getco,

how many types method in earth testing?

3 Answers   ONGC,

what is the interrelation between voltage current torgue speed and magnetic flux in case of different types of electric motors

0 Answers  

what is rated current and operating current?

3 Answers  

What is the purpose of SOTF being used inspite of distance Protection given?

7 Answers   Alstom,

which strater used genearalyy???and why???

1 Answers  

why ohms law does not obey semi-conducters?

2 Answers  

sir i used 3 hp of motor for spraying pump, other home light and other home items which size of allminium pvc wire ix used

0 Answers